Small type electromagnetic contactor

ABSTRACT

A small type electromagnetic contactor wherein a turning frame is rotatably bridged between a pair of opposing slots in a case having a build-in electromagnetic device, and actuating arm of an actuating rod member slidably mounted in an upper case member is disposed to be in contact with said turning frame.

United States Patent Usui et al.

Seto; Toshikltsu Hatakeynma, Owari Asahi, all of Japan Assignee: Matsushita Electric Works, Ltd., Osaka,

Japan Filed: Aug. 30, 1971 Appl. No.: 175,833

Foreign Application Priority Data 51 June 20, 1972 Primary Examiner-Harold Broome Attorney-Wolfe, Hubbard, Leydig, Voit & Osann. Ltd.

[5 7] ABSTRACT A small type electromagnetic contactor wherein a turning Aug. 3 l 1970 Japan ..45/7697l frame is rotatably bridged between a pair of opposing slots in a case having a build-in electromagnetic device, and actuating US. Cl 335/ 126, 335/132 arm of an actuating rod member slidably mounted in an upper Int- Clcase member is disposed to be in ontact with said turning Field of Search ..335/l06, 126, 131, 132, 202, fr

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sum 3 or a INVENTORS A ORNEYJ' SMALL TYPE ELECTROMAGNETIC CONTACTOR 1 DISCLOSURE OF THE INVENTION This invention relates to small type electromagnetic contac- IOIS.

The small type electromagnetic contactor in which an exciting coil is energized to attract a plunger and its movement is transmitted to movable contacts through a turning frame member to bring them into contact with fixed contacts, has been known as, for example, in US. Pat. No. 2,794,882. In this typeof contactor, since the plunger and a certain connecting lever are mechanically coupled with each other and are housed in a case, there have been required complex works to assemble such contactors.

According to this invention, the turning frame is rotatably bridged between a pair of opposing internal slots in the case, the head of the plunger is brought into contact with one side of the turning frame, and an extruded stub member disposed on the actuating rod for opening and closing the contacts is brought into engagement with the other side of the turning frame. Thus, without using any means for mechanically coupling between the plunger and the turning frame and further between the turning frame and the actuating rod, it is readily possible to assemble the electromagnetic contactor.

A principal object of the present invention is to provide an electromagnetic contactor in which the mechanical coupling between the plunger, turning frame and actuating rod is eliminated and thus the assembly of the same is easy.

Another object of this invention is to provide an electromagnetic contactor in which the contacts contained in the upper member can'be easily replaced.

The present invention shall now be explained in detail with reference to accompanying drawings, in which:

FIG. 1 is a sectional view showing an electromagnetic contactor embodying this invention;

FIG. 2 is a perspective view showing the structure of the upper member with an actuating rod disassembled;

FIG. 3 is a perspective view showing the turning frame; and

FIG. 4 is a perspective view showing the electromagnetic deviceand lower case member disassembled.

In FIG. 1, the reference A denotes an upper case member, in which fixed contacts, an actuating rod equipped with movable contacts, and a coil spring for biasing the actuating rod. The reference B denotes the main body, in which an electromagnetic device comprising a plunger, a yoke and a coil, a cushion member for absorbing any mechanical shocks produced in the electromagnetic device, and a turning frame which is rotated by the movement of said plunger. The contactor is assembled by placing the upper member A on the body B through an insulative plate 31.

FIG. 2 shows the upper member, wherein 1 is a case made of an insulating material, 2 is a plurality of fixed contacts, and 3 is a corresponding number of fixed plates having the fixed contacts 2. The fixed contacts 2 and fixed plates 3 are secured integral to said case 1. The internal space of said case 1 is divided into several numbers of small chambers 5 by a plurality of partition walls 4 and 4' projected from longitudinal both side walls toward the center. The fixed plates 3 are respectively secured to each of two mutually opposite sides in the chamber 5. These plates 3 are projected out of the case 1 to serve as terminals. As open path 6 is formed at the center of the partitions 4 and 4', and an actuating rod 7 is slidably disposed in the path 6. 30 is a lug disposed on each edge of an opening of the insulative case I.

Said actuating rod 7 is made of a synthetic resin, one end of which has an actuating arm 8 projected sideways. A recess 9 in which a coil spring 10 is inserted is provided at an end of the rod at the side where the actuating arm 8 is installed, and laterally opened windows 11 are provided in the rod body. A movable contact plate 12 is inserted into each of the windows 11. A movable contact 13 is disposed at each end of said movable contact plate 12. 14 is a coil spring contained in each window 11, by which spring the movable plate 12 is biased.

The actuating rod 7 thus equipped with the movable contact plates is slidably mounted in the open path 6 inside the case of the upper member so that the respective movable contacts will oppose to the respective fixed contacts.

FIG. 3 shows the turning frame 15, wherein mutually parallel arms 17 and 17' are provided as projected from both ends of main body 16, pivoting shafts 18 and 18 are disposed outside the arms 17 and 17', and hook members 19 and 19' are provided to further extend from the ends of the arms 17 and 17'.

FIG. 4 shows the main body of the contactor, wherein a vertical slot 21 is disposed inside each of opposing side walls of a case 20 which is made of an insulating material. An arcuate recess 22 is formed at each bottom end of said slots 21. Another pair of vertical slots 23 is disposed on the walls at opposite side to the slot 22. The reference 24 denotes an electromagnetic device, in which 25 is a yoke, 26 is a plunger, 27 is a connecting pin inserted through the head of the plunger, 28 is a coil, and 29 is a cushion member made of an elastic material such as rubber mounted to each side edge of the yoke. The electromagnetic device 24 having the cusion members 29 and the plunger 27 is inserted into the case 20 from its open side.

In assembling the respective parts, after the above assembling of the electromagnetic device 24 into the case 20, the turning frame 15 is housed in the case, and the pivoting shafts 18 and 18' of the frame are slidably set in the recesses 22. In this step of the assembly, the hook members 19 and 19 of arms 17 and 17' of the turning frame 15 are brought into contact with the connecting pin 27 of the plunger 26. The upper member A is placed on the case 20. In this step, the operating arm 8 of the actuating rod 7 is brought into contact with the left shoulder part of the main body 16 as shown in FIG. 1. The respective lugs 30 of the upper case 1 are fitted in the respective slots 21 so as to secure the shafts 18 of the frame 15 in position.

The small type electromagnetic contactor of this invention is operated in the following manner. FIG. 1 shows the state where the plunger 26 is not attracted and the fixed contacts 2 are away of the movable contacts 13, namely in the OFF state. In this state, when the coil 28 is energized, the plunger 26 is attracted and moved in the direction of X, the turning frame 15 is rotated about the shafts l8, and the actuating arm 8 of the actuating rod 7 is moved toward the direction of Y as urged by the main body 16 of the frame 15. As a result, the movable contact plates 13 are moved in the Y-direction and brought into contact with the fixed contacts 2 to establish the ON state.

When the coil 28 is deenergized, the actuating rod 7 is moved in the direction opposite to the Y-direction by the force of the return spring 10, so that the respective contacts are opened and the plunger 26 is returned to initial position.

According to the present invention, as has been described above, the electromagnetic contactor is divided chiefly into two parts of the upper member section equipped with the electric contacts opened and closed by the actuating rod, and the main body section in which the electromagnetic device comprising a yoke, a coil and a plunger is contained, and the arrangement is such that, in order to transmit the actuating force produced when the plunger is attracted to said operating rod, only such a single member as the turning frame is inserted in the open slots in the main body section and, thereby, the plunger in said section and the actuating rod in the upper section are operatively coupled. In conventional contactors, on the other hand, even they comprise chiefly the upper member and the main body, the turning frame is connected to the plunger by pin, lever and the like, which plunger is installed in the body case prior to said connection. This is why complicated procedures have been required in the assembly process for mechanically coupling the plunger, turning frame and actuating rod when installing the electromagnetic device in the main case or assembling the upper member. The present invention has effectively solved all these problems in a simple manner.

According to the present invention, the material of the tuming frame is not limited to any. For example, if the turning frame is made of a magnetic material, the frame will effectively serve to reduce the magnetic loss between the yoke and plunger as a part of the electromagnetic device, depending on the shape of the frame.

What is claimed is:

l. A small type electromagnetic contactor comprising an upper member which comprises a case opened at one side, a plurality of fixed contacts secured integral to said case, an actuating rod having a plurality of movable contacts respectively arranged to face each said fixed contact, said actuating rod being disposed slidably along a path in the case at said opened side and provided with an actuating arm projected at an end and outside the case, and a means for biasing said actuating rod in opening direction of the contacts; and

a main body member which comprises a case opened at one side, an electromagnetic device contained in said case, a plunger slidably mounted in said electromagnetic device, said plunger being extended at a head out of the device, a connecting pin provided at said head of the plunger, and a turning frame having a shoulder part and a hooking part and pivotably mounted in an open slot disposed inside the case, said hooking part being engaged with said connecting pin of the plunger;

said upper member being superposed on the open side of the case of said main body so that the actuating arm of the actuating rod will engage said shoulder part of said turning frame, whereby an energization of the electromagnetic device will cause the turning frame to be pivotally turned by the connecting pin of the plunger attracted so as to urge the actuating arm of the actuating rod with the shoulder part of the frame in closing direction of the contacts.

2. An electromagnetic contactor according to claim 1, wherein said turning frame comprises mutually parallel arms disposed on both sides of a main body, pivoting shafts disposed outside said arms, and hook members disposed at the ends of said arms.

3. An electromagnetic contactor according to claim 1, in

which said actuating arm of the actuating rod is brought into contact with the turning frame substantially at the center of its main body.

4. An electromagnetic contactor according to claim 1, in

which said pivoting shafts of the turning frame are rotatably engaged respectively in vertically opened slots disposed on the internal side walls of the lower case, and each upper part of said open slot is covered with a projection from the upper case member. 

1. A small type electromagnetic contactor comprising an upper member which comprises a case opened at one side, a plurality of fixed contacts secured integral to said case, an actuating rod having a plurality of movable contacts respectively arranged to face each said fixed contact, said actuating rod being disposed slidably along a path in the case at said opened side and provided with an actuating arm projected at an end and outside the case, and a means for biasing said actuating rod in opening direction of the contacts; and a main body member which comprises a case opened at one side, an electromagnetic device contained in said case, a plunger slidably mounted in said electromagnetic device, said plunger being extended at a head out of the device, a connecting pin provided at said head of the plunger, and a turning frame having a shoulder part and a hooking part and pivotably mounted in an open slot disposed inside the case, said hooking part being engaged with said connecting pin of the plunger; said upper member being superposed on the open side of the case of said main body so that the actuating arm of the actuating rod will engage said shoulder part of said turning frame, whereby an energization of the electromagnetic device will cause the turning frame to be pivotally turned by the connecting pin of the plunger attracted so as to urge the actuating arm of the actuating rod with the shoulder part of the frame in closing direction of the contacts.
 2. An electromagnetic contactor according to claim 1, wherein said turning frame comprises mutually parallel arms disposed on both sides of a main body, pivoting shafts disposed outside said arms, and hook members disposed at the ends of said arms.
 3. An electromagnetic contactor according to claim 1, in which said actuating arm of the actuating rod is brought into contact with the turning frame substantially at the center of its main body.
 4. An electromagnetic contactor according to claim 1, in which said pivoting shafts of the turning frame are rotatably engaged respectively in vertically opened slots disposed on the internal side walls of the lower case, and each upper part of said open slot is covered with a projection from the upper case member. 